Heretofore, there have been various article positioning fixtures provided for positioning a plurality of test articles in a fixture so that a common machining of finishing operation can be performed on the so positioned test article. Specifically, an open center or hollow fixture has been made from a top plate, a pair of side plates, and a bottom or spacer plate. The top plate has a locating groove extending axially of the fixture and a plurality of inserts or plates are positionable on the fixture to engage the locating groove to be accurately located in the fixture. These locator inserts are adpated to engage and position a matrix box in which a test article or article blank is operatively positioned. The fixture can have a plurality of the matrix boxes individually secured to locator inserts operatively secured to the fixture. The matrix boxes have the test articles positioned in accurately aligned relation so a common machining or grinding operation can be performed on exposed portions, such as ends, of the test articles. This type of an article positioning fixture facilitates machining operations and the production of uniform articles by efficient use of machine action. Of course, the test articles are accurately located in the matrix box and this is provided in known manners by use of other means such as the article centering or balancing construction shown in my prior U.S. Pat. No. 2,999,282.
By making these blocks or fixtures from a plurality of parts, it has been difficult to maintain them in good operative, accurate relationships over a long service life. Furthermore, the locator inserts used in the apparatus have been subject to appreciable wear by the repeated application of a matrix box thereto, securing the matrix block or box to the locator insert, and then the removal of the matrix block from the apparatus. Obviously, a large number of test articles will be positioned in the fixture over a long service life and the attachment and release of the matrix boxes to and from the fixture does cause appreciable wear. For accuracy in maintaining the fixture components in proper relationship with each other, frequently the locator inserts must be replaced, or other repairs made thereto, to keep the fixture functioning accurately and exactly as required.